For heating devices or cooktops (e.g., hobs), it is known that they operate in a first operating mode cooking utensils and their contents are heated at temperatures above 200° C. (e.g. boiling foods or frying). In a second operating mode, it is possible to keep a cooking container and its food hot at a lowerpower level and temperature well below 100° C., i.e. without boiling. In the first mode the cooktop surface is protected against damage by reaching high temperatures by means of a mechanical temperature detection device, also known as a rod controller. Such rod controllers are e.g. known from U.S. Pat. No. 5,113,170 or DE-A-102004023787 and have a switching point in a range 500 to 600° C. The heating device is switched then off on reaching or exceeding the same temperature. Another switching point is defined in the form of a so-called “hot” indication at approximately 70° C. This indicates by means of a lamp or the like to an operator when the hob is too hot for contact.
Thus, there is a need to provide such a device and method enabling the problems of the prior art to be avoided and so as to, in particular, permit a better control or regulation of a heating device, particularly in different operating modes.